张勤进;庄绪州;刘彦呈;王川;

• 1:大连海事大学轮机工程学院

摘要(Abstract)：

实现微源间负荷电流的精确分配及母线电压的无差调节是直流微电网重要的控制目标,但由于线路阻抗及低速通信的存在,传统下垂控制很难同时满足均流及稳定性的要求。提出一种基于低频低幅值交流信号注入的多源并联自主均流控制策略,在各变流器直流输出上注入交流小信号,并使其频率与输出直流电流产生频率–电流下垂特性,利用产生的无功功率环流调节各变流器输出直流电压,进而在反馈机制下,实现多变流器间的并联控制及负荷电流的精确分配;在此基础上,利用限幅及负阻抗环节,提出一种改进的母线电压补偿方法,进一步降低了由于线路阻抗造成的电压跌落,该方法无需互联通信线,无需改变硬件结构,易于实现;最后利用小信号建模,分析了控制策略的稳定性和动态性能。仿真和实验验证了所提方法的可行性和有效性。

关键词(KeyWords)： 直流微电网;均流控制;注入交流电压;母线电压调节;虚拟负阻抗

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金(51709028,51979021);; 辽宁省自然科学基金项目(20170540082);; 中央高校基本科研业务费专项资金(3132018262)~~

作者(Author): 张勤进;庄绪州;刘彦呈;王川;

Email:

DOI: 10.13335/j.1000-3673.pst.2019.1664

参考文献(References)：

• [1]李霞林,郭力,王成山,等.直流微电网关键技术研究综述[J].中国电机工程学报,2016,36(1):2-17.Li Xialin,Guo Li,Wang Chengshan,et al.Key technologies of DC microgrids:an overview[J].Proceedings of the CSEE,2016,36(1):2-17(in Chinese).
• [2]厉泽坤,孔力,裴玮,等.基于混合势函数的下垂控制直流微电网大扰动稳定性分析[J].电网技术,2018,42(11):3725-3734.Li Zekun,Kong Li,Pei Wei,et al.Large-disturbance stability analysis of droop-controlled dc microgrid based on mixed potential function[J].Power System Technology,2018,42(11):3725-3734(in Chinese).
• [3]刘胜,程垠钟.基于小信号模型的船舶中压直流发电系统稳定性分析[J].中国电机工程学报,2015,35(8):1930-1939.Liu Sheng,Cheng Yinzhong.Small signal model based stability analysis for shipboard medium voltage DC generation systems[J].Proceedings of the CSEE,2015,35(8):1930-1939(in Chinese).
• [4] Yan B K,Wang B,Zhu L,et al.A novel,stable,and economic power sharing scheme for an autonomous microgrid in the energy internet[J].Energies,2015(8):2741-2764.
• [5]于明,王毅,李永刚.基于预测方法的直流微网混合储能虚拟惯性控制[J].电网技术,2017,41(5):1526-1532.Yu Ming,Wang Yi,Li Yonggang.Virtual inertia control of hybrid energy storage in DC microgrid based on predictive method[J].Power System Technology,2017,41(5):1526-1532(in Chinese).
• [6] Zhang Q J,Liu Y C,Zhao Y T,et al.A multi-mode operation control strategy for flexible microgrid based on sliding-mode direct voltage and hierarchical controls[J].ISA Transactions,2016(61):188-198.
• [7] Castilla M,Camacho A,Miret J,et al.Local secondary control for inverter-based islanded microgrids with accurate active power sharing under high-load conditions[J]. IEEE Transactions on Industrial Electronics,2019,64(4):2529-2539.
• [8] Li P,Lehman B.A design method for paralleling current-modecontrolled DC-DC converters[J]. IEEE Transactions on Power Electronics,2004,19(3):35-43.
• [9]涂春鸣,熊诵辉,肖凡,等.基于电流跟踪的多直流微源并联运行主从控制策略[J].电网技术,2017,41(7):2205-2213.Tu Chunming,Xiong Songhui,Xiao Fan,et al.Master-slave control strategy for parallel operation of multiple DC micro-source based on current tracking[J]. Power System Technology, 2017, 41(7):2205-2213(in Chinese).
• [10] Cavraro G,Caldognetto T,Carli R,et al.A master/slave approach to power flow and overvoltage control in low-voltage microgrids[J].Energies,2019,12(14),2760.
• [11] Jin G B,Li L,Li G Q,et al.Accurate proportional load sharing among paralleled inverters based on improved P-V droop coefficient[J].Electric Power Systems Research,2017(143):312-320.
• [12] Xiao J F, Setyawan L, Wang P, et al. Power-capacity-based bus-voltage region partition and online droop coefficient tuning for real-time operation of DC microgrids[J]. IEEE Transactions on Energy Conversion,2015,30(4):1338-1347.
• [13] Wu D,Tang F,Dragicevic T,et al.Coordinated control based on bus-signaling and virtual inertia for islanded DC microgrids[J].IEEE Transactions on Smart Grid,2015,6(6):2627-2638.
• [14] Morstyn T,Hredzak B,Demetriades G D,et al.Unified distributed control for DC microgrid operating modes[J].IEEE Transactions on Power Systems,2016,31(1):802-812.
• [15] Lee G Y,Ko B S,Cho J,et al.A distributed control method based on a voltage sensitivity matrix in DC microgrids with low-speed communication[J].IEEE Transactions on Smart Grid,2019,10(4):3809-3817.
• [16] Dragicevic T,Guerrero J M,Vasquez J C.A distributed control strategy for coordination of an autonomous LVDC microgrid based on power-line signaling[J].IEEE Transactions on Industrial Electronics,2014,61(7):3313-3326.
• [17] Liu B J,Liu Z,Liu J J,et al.An adaptive virtual impedance control scheme based on small-AC-signal injection for unbalanced and harmonic power sharing in islanded microgrids[J].IEEE Transactions on Power Electronics,2019,34(12):12333-12355.
• [18] Peyghami S,Davari P,Mokhtari H,et al.Synchronverter-enabled DC power sharing approach for LVDC microgrids[J].IEEE Transactions on Power Electronics,2017,32(10):8089-8099.
• [19]郭力,冯怿彬,李霞林,等.直流微电网稳定性分析及阻尼控制方法研究[J].中国电机工程学报,2016,36(4):927-936.Guo Li,Feng Yibin,Li Xialin,et al.Stability analysis and research of active damping method for DC microgrids[J].Proceedings of the CSEE,2016,36(4):927-936(in Chinese).
• [20]李宁宁,梁爽,纪延超,等.基于LCL滤波器的蓄电池双向DC/DC变换器的研究[J].电机与控制学报,2015,19(7):8-13.Li Ningning,Liang Shuang,Ji Yanchao,et al.Research on battery DC/DC bidirectional converter using LCL filter[J].Electric Machines and Control,2015,19(7):8-13(in Chinese).